Authors:

Alyssa McKenna
(Mount Holyoke College)

Myunghwan Byun
(University of Massachusetts Amherst)

Ryan Hayward
(University of Massachusetts Amherst)

Katherine Aidala
(Mount Holyoke College)

Stimuli-responsive hydrogel films formed from photo-crosslinkable polymers
are versatile materials for controlled drug delivery devices,
three-dimensional micro-assemblies, and components in microfluidic systems.
For such applications, it is important to understand both the mechanical
properties and the dynamics responses of these materials. We describe the
use of atomic force microscope (AFM) based indentation experiments to
characterize the properties of poly($N$-isopropylacrylamide) copolymer films,
crosslinked by activation of pendent benzophenone units using ultraviolet
light. In particular, we study how the elastic modulus of the material,
determined using the Johnson, Kendall, and Roberts model, depends on UV
dose, and simultaneously investigate stress relaxation in these materials in
the context of viscoelastic and poroelastic relaxation models.

To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2012.MAR.P47.11